Defect-related degradation in InGaN laser diodes

The paper describes an extensive analysis of the degradation of InGaN-based laser diodes submitted to constant stress at room temperature. The analysis is based on electrical and optical characterizations, deep level transient spectroscopy (DLTS) and capacitance measurement as function of temperature. The results obtained during the stress demonstrate: (i) the presence of a diffusion process in the first hours of stress; (ii) an increase in the junction capacitance, and so of the free charge, with the aging of the device; (iii) the presence of shallow traps, in particular an acceptor like trap, associated with line defects.